About Spire Codex

Spire Codex is a comprehensive database for Slay the Spire 2, commonly abbreviated StS2, built by reverse-engineering the game files. Every card, relic, monster, potion, event, and power on this site was extracted directly from the game's source code and localization data.

The project started from curiosity about how StS2 was built, and grew into a full API and website. The goal is to provide the kind of detailed, searchable reference that the Spire community deserves.

If you're wanting to get involved, feel free to open a PR on GitHub. This repo is downstream of where the project is hosted, so it may take a bit before your PR gets fully merged. The project has an open API that is free to use and self-hostable. And if you're wanting to chat about the project, come visit the Discord where I send updates and discuss the project.

Big thanks to everyone supporting the project, see the Thank You page for Ko-fi supporters and community contributors.

What's Inside

How It Works

Slay the Spire 2 is built with Godot 4, but all game logic lives in a C#/.NET 8 DLL. The data pipeline:

PCK Extraction

GDRE Tools extracts the Godot .pck file, images, Spine animations, localization data (~9,947 files)

DLL Decompilation

ILSpy decompiles sts2.dll into ~3,300 C# source files containing all game models

Data Parsing

17 Python parsers extract structured data from decompiled C# source + localization JSON

Spine Rendering

Headless Node.js renderer assembles skeletal animations into 512×512 portrait PNGs (130+ sprites)

API + Frontend

FastAPI serves parsed data as a REST API with 20+ endpoints; Next.js frontend consumes it

Features

Detail Pages

Click-through pages for cards, characters, relics, monsters, and potions with full stats

Global Search

Press . anywhere to search across all categories instantly

Rich Text Rendering

Game BBCode tags rendered with colors, animations, and inline icons

Character Dialogues

NPC conversation trees and character quotes from the game's localization

Spine Renders

130+ monster and character sprites rendered from skeletal animations

REST API

Full API with filtering, search, and Swagger docs for your own projects

Changelog Tracking

Field-level diffs between game updates across all categories

Image Downloads

Browse and download all extracted game art by category

Tech Stack

Backend

Python, FastAPI, Pydantic

Frontend

Next.js, TypeScript, Tailwind

Rendering

Node.js, Playwright, spine-webgl

Infra

Docker, Forgejo CI

This project is for educational purposes. All game data belongs to Mega Crit Games. This should not be used to recompile or redistribute the game.